Production of halonitroethanes



"' 4 2,928,883 Patented Mar. 15, 1980 PRODUCTION OF HALONITROETHANES No Drawing. Application June 20, 1958 Serial No. 743,494

9 Claims. (Cl. 260-644) 'Our invention relates to the production of halonitroethanes and more particularly it relates to the liquid phase halonitration of haloethylenes to produce halonitroethanes having at least one halogen beta to the carbon carrying the nitro radical. Unsubstituted olefins have previously been shown to react with mixtures of-halogens and dinitrogen tetroxide to form the corresponding beta-haloalkyl nitrates (G. B. Bachman and T. J. Logan, J. Org. Chem., .21, 1467 (1956)). We have now discovered that halogen sub stituted olefins, in particular, vinyl chloride, vinyl bromide, vinylidene chloride, etc, react with these same halogen-dinitrogen tetroxide mixtures to produce nitroethanes having at least one halogen .beta to the carbon carrying thenitro radical. The different products obtainedin go+ ing from an unsubstituted olefin such as ethylene to a substituted olefin such as vinyl chloride apparentlyarises from an unexpected difierence in the mechanism of the attack on the double bond. Our process for the production of nitroethanes having at least one halogen beta to the carbon carrying the nitro radical consistsessentially of adding a halogenated ethylene to a solution of liquid dinitrogen tetroxide and chlorine, bromine or iodine. The reaction may be carried out utilizing the liquid dinitrogen tetroxide as a solvent for the halogen, or we may use a neutral halogenated ever, can be varied somewhat. Mole ratios of dinitrogen tetroxide ranging from 0.2 to 0.5 mole to 0.1 to 0.5 mole of halogen have given satisfactory results. We prefer to use a solution containing a mole ratio-of halogen to dinitrogen tetroxide of 1.0 or less.

The nitroethanes having at least one halogen beta to the carbon carrying the nitro radical of our invention are useful as solvents for various purposes, and particularly as soil fumigants, being readily sprayed onto or introduced into the soil in the manner and in the amount customarily employed in soil fumigation.

A better understanding of the nature of our invention can be had by reference to the following examples which illustrate our invention. We do not intend to be limited to the procedures, amounts and conditions set forth in the examples, but we intend for equivalents and variations obvious to those skilled in the art to be included within the scope of this specification and the attached claims.

Example I Chlorine was passed into 221 ml. of carbon tetra chloride maintained at 0 0. until 17.7 'g. 0.25 mole) had dissolved. Liquid dinitrogen tetroxide, 15.3 ml. (0.25 mole) was then added and the solution thoroughly mixed.

Vinyl bromide was then passed into this solution for 180 minutes while the temperature was maintained at 0 C., by both internal and external cooling. The resultant light-brown solution was washed eight times with ml. portions of water. The organic layer became almost yellow-orange. Removal of the solvent and fractionation gave 14.3 g.- of 1,2-dichloro-l bromoethane,

B.P. 35 C. (3.0 mm.), and 39.0 g. of liquid, B.P"47-8 C (1.0-2.0 mm.). This'latter fraction was redistilled to give l-bromo-l-chloro-Z-nitroethanerboiling at 48 C. (1.2 mm.) n 1.5070, 82.8% conversion based on dinitrogen tetroxide.

solvent such as chloroform or carbon tetrachloride, or a liquid nitroalkane or. other solvent which can advantageously be employed as a solvent for both' the liquid dinitrogentetroxide and'the halogen, and whichdoes not react under the conditions employed; When the solution will no longer absorb the halogenated ethylene, the prodnets are water extracted, dried, and fractionally distilled at reduced pressures to remove any of the products formed in the reaction.

In carryingiout our process, we can. use vinyl chloride, vinyl bromide, and the corresponding diand tri-halo substituted ethylenes such as 1,2-dichloroethylene, vinylidene chloride, trichloroethylene, dibromoethylene, vinylidene bromide, and tribromoethylene, dinitrogen tetroxide, and the halogens chlorine, bromine and iodine.

The reaction iscarried out in the liquid phase at temperatures preferably ranging from 10 C. to +25 C. The reaction can be carried out by preparing a solution of the desired halogen in the dinitrogen tetroxide and then passing the halogenated ethylene into the resulting mixture maintained at the desired reaction temperature.

Preferably, however, we dissolve the required amounts Analysis.--Calculated for C H ClBrNO C, 12.74; H, 1.60; N, 7.43. Found: C, 13.85; H, 1.73; N, 7.25.

The anthranilic acid derivative of the liquid melted with decomposition at 1989 C.

Example II- to 0 C. and vinyl chloride then passed into it until no more reaction was evident. At this .point, the solution was clear brown and .had a volume of 375 ml. The solution was allowed to warm to room temperature overnight andthen had a bright green color. 'Severalwashing's with ice water and removal of most of the solvent gave 116 ml. of a light yellow, highly lacrymatory liquid which yellowed the skin on contact. Distillation of 25 ml. of this liquid gave 11.8 ml. of 1,Z-dibromo-l-chloroethane, B.P. 44 C. (4.0 mm.), and 16.1 g. of I-bromo-l-chloro- Z-nitroethane, B.P. 41 C- (0.5 mm.), 11 1.4980, 11 1.861. This represented a 79.5% conversion to crude product, based on dinitrogen tetroxide.

Analysis-Calculated for C H BrClNO C, 12.71; H, 1.59; N, 7.43. Found: C, 12.47; H, 1.89; N, 7.70.

Example III Into the reactor was placed 25.4 g. (0.1 mole) of powdered iodine and 12.3 ml. (0.2 mole) of dinitrogen tetroxide in 600 ml. of chloroform. Vinyl chloride was then bubbled into the solution at a rate of approximately 0.9 g./minute while maintaining the solution at a temperature of approximately 15 C. The deep iodine colored solution became clear green after 15 minutes. This green solution was decanted from the unreacted iodine (5 g.). The solvent was removed and there remained 23.5 ml. of an orange liquid which weighed 42.8 g. A

3 2.0 ml. aliquot of this liquid gave 2.178 g. of anthranilic acid derivative, M.P. 198-200 (dec.). Using this weight of derivative, the conversion based on iodine to l-chlorol-iodo-2-nitroethane was 61.5%. Attempts to distill the product led only to decomposition with loss of iodine.

Example IV A flask containing 442 ml. of carbon tetrachloride was immersed in a salt-ice mixture and chlorine (36 g., 0.5 mole) was introduced into the carbon tetrachloride at C. until the solvent was saturated. Liquid dinitrogen tetroxide (61.4 ml., 1.0 mole) was added and then 96.7 g. (1.0 mole) of a mixture of cisand trans-1,2-dichloroethylene slowly added over a period of two hours with stirring. The mixture was then allowed to stand at 0 C. for 12 hours and then washed with ice and water until a light yellow colorresulted and finally dried with Drierite. Distillation yielded unreacted trans-l,Z-dichloroethylene, 34.1 g. B.P. 48 C., 1,l,2trichloro-Z-nitroethane, 17.0 g. B.P. 32 C. (1.5 mm.), n 1.4867, and a viscous yellow residue, 20.2 g., n 1.4922.

Example V Carbon tetrachloride(442 ml.) was cooled to 0 C. by

asalt-ice mixture and saturated with chlorine (0.50 mole). Liquid dinitrogen tetroxide (61.4 ml., 1.0 mole) was added thereto followed by dropwise addition of vinylidene chloride (80 g., 0.83 mole) over a period of two hours. The mixture was allowed to stand without stirring for an additional five hours andithen washed with ice and water until a pale blue color resulted and finally dried'with Drierite. After the, solvent had been removed by distillation 32.2 g..o 1,1,1,-trichloro-2-nitroethane having a boiling point of 55 C. (2.0 inn-1.), and n 1.4839 was. obtained together withv 39.3 g. of a viscous dark-yellow residue. v

Example VI Into a reaction flask was placed 1326 ml. of carbon tetrachloride and 106.5 g. (1.5 mole) of chlorine was then added, the temperature being maintained at 0 C. After 184.2 ml. 3.0 mole) of dinitrogen tetroxide had been added, trichloroethylene (394.2 g., 3.0 mole) was slowly added over a period of two hours with stirring. The resulting mixture was allowed to stand for 66 hours after which it was washed with ice and water and dried with Drierite. Eollowing solvent removal, distillation gave 1,1,2-triehloroa2rnitroethylene, 26.2 g., B.P. 37 C. (5.5 mm.), u 1.5095; 1,1,2,2-tetrachloro Z-nitroethane 26.8 g.,'B.P."5,0 C. (4.0 mm), 12 1.4965; and dark red-brown viscous residue (186.7 g.)

Now having described our invention, what we claim is:

1 In a process for the halonitration of halogenated ethylenes, the step whichcomprises reacting in the liquid phase at temperatures rangingfrom 10 C. to

C. a material selected from the group consisting of chlorinated ethylenes and brominated ethylenes with dinitrogen tetroxide and a halogen selected from the group consisting of bromine, chlorine and iodine.

2. The process of claim 1 wherein said halonitration is effected in the presence of an inert solvent.

3. The process of claim 1 wherein the halogenated ethylene is slowly added to a mixture of dinitrogen tetroxide and a halogen selected from the group consist ing of bromine, chlorine and iodine.

4. In a process for the production of l-bromo-l-chloro- 2-nitroethane by the halonitration of vinyl chloride, the step which comprises slowly adding vinyl chloride to a solution of dinitrogen tetroxide andbromine in carbon tetrachloride while maintaining the reaction mixture at a temperature of approximately 0 C.

5. In a process for the production of l-bromo-l-chloro- Z-nitroethane, by the halonitration of vinyl bromide, the step which comprises slowly adding vinyl bromide to a mixture of dinitrogen tetroxide and chlorine in carbon tetrachloride while maintaining the solution at a temperature of approximately 0 C.

6. In a process for the production of l-chloro-l-iodo- 2-nitroethane by the halonitration of vinyl chloride, the step which comprises slowly adding vinyl chloride to a mixture of dinitrogen tetroxide and iodine in chloroform while maintaining the reaction mixture at a temperature of approximately 15 C.

7. In a process for the production of 1,1,2-trichloro- 2-nitroethane by the halonitration of 1,2-dichloroethylene, the step which comprises slowly adding 1,2-dichloroethyleneto a mixture of dinitrogen tetroxide and chlorine incarbon tetrachloride while maintaining the reaction mixture at a temperature of approximately 0 C.

8. In a process for the production of 1,l,l-trichloro- Z-nitroethane by the halonitration of vinylidene chloride, the step which comprises slowly adding vinylidene choride to a mixture of dinitrogen tetroxide and chlorine in carbon tetrachloride while maintaining the temperature of the reaction mixture at approximately 0 C.

9. In a process for the production of 1,l,2,2-tetra.- chloro-Z-nitroethane by the halonitration of trichloroethylone, the step which comprises slowly adding trichloroethylene to a mixture of dinitrogen tetroxide and chlorine in carbon tetrachloride while maintaining thetemperature of the reaction mixture at approximately 0 C.

References Cited in the filerof this patent FOREIGN PATENTS Netherlands Feb. 15, 1947 

1. IN A PROCESS FOR THE HALONITRATION OF HALOGENATED ETHYLENE, THE STEP WHICH COMPRISES REACTING IN THE LIQUID PHASE AT TEMPERATURES RANGING FROM -10*C. TO +25* C. A MATERIAL SELECTED FROM THE GROUP CONSISTING OF CHLORINATED ETHYLENES AND BROMINATED ETHYLENES WITH DINITROGEN TETROXIDE AND A HALOGEN SELECTED FROM THE GROUP CONSISTING OF BROMINE, CHLORINE AND IODINE, 